﻿<!DOCTYPE html>
<html lang="en">
<head>
	<title>three.js webgl - instancing test (single triangle)</title>
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
	<style>
		body {
			color: #ffffff;
			font-family: Monospace;
			font-size: 13px;
			text-align: center;
			font-weight: bold;
			background-color: #000000;
			margin: 0px;
			overflow: hidden;
		}

		#info {
			position: absolute;
			top: 0px;
			width: 100%;
			padding: 5px;
		}

		a {
			color: #ffffff;
		}

		#oldie a {
			color: #da0;
		}

		#notSupported {
			width: 50%;
			margin: auto;
			border: 2px red solid;
			margin-top: 20px;
			padding: 10px;
		}
	</style>
</head>
<body>

	<div id="container"></div>
	<div id="info">
		<a href="http://threejs.org" target="_blank">three.js</a> - instancing demo (single triangle)
		<div id="notSupported" style="display:none">Sorry your graphics card + browser does not support hardware instancing</div>
	</div>

	<script src="js/libs/dat.gui.min.js"></script>
	<script src="../build/three.js"></script>
	<script src="js/Detector.js"></script>
	<script src="js/libs/stats.min.js"></script>

	<script id="vertexShader" type="x-shader/x-vertex">
		precision highp float;

		uniform float sineTime;

		uniform mat4 modelViewMatrix;
		uniform mat4 projectionMatrix;

		attribute vec3 position;
		attribute vec3 offset;
		attribute vec4 color;
		attribute vec4 orientationStart;
		attribute vec4 orientationEnd;

		varying vec3 vPosition;
		varying vec4 vColor;

		void main(){

			vPosition = offset * max(abs(sineTime * 2.0 + 1.0), 0.5) + position;
			vec4 orientation = normalize(mix(orientationStart, orientationEnd, sineTime));
			vec3 vcV = cross(orientation.xyz, vPosition);
			vPosition = vcV * (2.0 * orientation.w) + (cross(orientation.xyz, vcV) * 2.0 + vPosition);

			vColor = color;

			gl_Position = projectionMatrix * modelViewMatrix * vec4( vPosition, 1.0 );

		}

	</script>

	<script id="fragmentShader" type="x-shader/x-fragment">

		precision highp float;

		uniform float time;

		varying vec3 vPosition;
		varying vec4 vColor;

		void main() {

			vec4 color = vec4( vColor );
			color.r += sin( vPosition.x * 10.0 + time ) * 0.5;

			gl_FragColor = color;

		}

	</script>

	<script>

		if ( !Detector.webgl ) Detector.addGetWebGLMessage();

		var container, stats;

		var camera, scene, renderer;

		init();
		animate();

		function init() {

			container = document.getElementById( 'container' );

			camera = new THREE.PerspectiveCamera( 50, window.innerWidth / window.innerHeight, 1, 10 );
			camera.position.z = 2;

			scene = new THREE.Scene();

			// geometry

			var triangles = 1;
			var instances = 65000;

			var geometry = new THREE.InstancedBufferGeometry();

			geometry.maxInstancedCount = instances; // set so its initalized for dat.GUI, will be set in first draw otherwise
			var gui = new dat.GUI();
			gui.add( geometry, "maxInstancedCount", 0, instances );

			var vertices = new THREE.BufferAttribute( new Float32Array( triangles * 3 * 3 ), 3 );

			vertices.setXYZ( 0, 0.025, -0.025, 0 );
			vertices.setXYZ( 1, -0.025, 0.025, 0 );
			vertices.setXYZ( 2, 0, 0, 0.025 );

			geometry.addAttribute( 'position', vertices );

			var offsets = new THREE.InstancedBufferAttribute( new Float32Array( instances * 3 ), 3, 1 );

			for ( var i = 0, ul = offsets.count; i < ul; i++ ) {

				offsets.setXYZ( i, Math.random() - 0.5, Math.random() - 0.5, Math.random() - 0.5 );

			}

			geometry.addAttribute( 'offset', offsets );

			var colors = new THREE.InstancedBufferAttribute( new Float32Array( instances * 4 ), 4, 1 );

			for ( var i = 0, ul = colors.count; i < ul; i++ ) {

				colors.setXYZW( i, Math.random(), Math.random(), Math.random(), Math.random() );

			}

			geometry.addAttribute( 'color', colors );

			var vector = new THREE.Vector4();

			var orientationsStart = new THREE.InstancedBufferAttribute( new Float32Array( instances * 4 ), 4, 1 );

			for ( var i = 0, ul = orientationsStart.count; i < ul; i++ ) {

				vector.set( Math.random() * 2 - 1, Math.random() * 2 - 1, Math.random() * 2 - 1, Math.random() * 2 - 1 );
				vector.normalize();

				orientationsStart.setXYZW( i, vector.x, vector.y, vector.z, vector.w );

			}

			geometry.addAttribute( 'orientationStart', orientationsStart );

			var orientationsEnd = new THREE.InstancedBufferAttribute( new Float32Array( instances * 4 ), 4, 1 );

			for ( var i = 0, ul = orientationsEnd.count; i < ul; i++ ) {

				vector.set( Math.random() * 2 - 1, Math.random() * 2 - 1, Math.random() * 2 - 1, Math.random() * 2 - 1 );
				vector.normalize();

				orientationsEnd.setXYZW( i, vector.x, vector.y, vector.z, vector.w );

			}

			geometry.addAttribute( 'orientationEnd', orientationsEnd );

			// material

			var material = new THREE.RawShaderMaterial( {

				uniforms: {
					time: { value: 1.0 },
					sineTime: { value: 1.0 }
				},
				vertexShader: document.getElementById( 'vertexShader' ).textContent,
				fragmentShader: document.getElementById( 'fragmentShader' ).textContent,
				side: THREE.DoubleSide,
				transparent: true

			} );

			var mesh = new THREE.Mesh( geometry, material );
			scene.add( mesh );

			renderer = new THREE.WebGLRenderer();

			if ( renderer.extensions.get( 'ANGLE_instanced_arrays' ) === false ) {
				document.getElementById( "notSupported" ).style.display = "";
				return;
			}

			renderer.setClearColor( 0x101010 );
			renderer.setPixelRatio( window.devicePixelRatio );
			renderer.setSize( window.innerWidth, window.innerHeight );
			container.appendChild( renderer.domElement );

			stats = new Stats();
			container.appendChild( stats.dom );

			window.addEventListener( 'resize', onWindowResize, false );

		}

		function onWindowResize( event ) {

			camera.aspect = window.innerWidth / window.innerHeight;
			camera.updateProjectionMatrix();

			renderer.setSize( window.innerWidth, window.innerHeight );

		}

		//

		function animate() {

			requestAnimationFrame( animate );

			render();
			stats.update();

		}

		function render() {

			var time = performance.now();

			var object = scene.children[0];

			object.rotation.y = time * 0.0005;
			object.material.uniforms.time.value = time * 0.005;
			object.material.uniforms.sineTime.value = Math.sin( object.material.uniforms.time.value * 0.05 );

			renderer.render( scene, camera );

		}

	</script>

</body>

</html>
